This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The COPDGene Study is a 21-center, NIH / NHLBI funded study of 10,000 smokers, current or former, composed of individuals who meet the Global Initiative in Obstructive Lung Disease (GOLD) criteria for chronic obstructive pulmonary disease (COPD) and control subjects without lung impairment. The cohort is limited to two ethnic groups;7000 non-Hispanic whites and 3000 non-Hispanic African Americans. The specific aims are to 1) perform a genome-wide association study in each ethnic group to determine the genetic determinants of COPD susceptibility and other COPD-related phenotypes, 2) further characterize the airway and parenchymal phenotypes of COPD by determining their clinical, physiologic, functional indices, and 3) perform longitudinal follow-up to determine mortality, co-morbidities, and disease status based on clinical and /or chest CT evidence of progression.